Kubelet

kubelet process in Kubernetes is responsible for running containers on the node

• Configuration: /etc/kubernetes/kubelet.conf
• Logs: /var/log/kubelet.log
• Port: kubelet listen on port 10250

• Installation Ubuntu: snap install kubelet --classic (snap stop kubelet.daemon or snap start kubelet.daemon)

Commands

systemctl start snap.kubelet.daemon.service
systemctl stop snap.kubelet.daemon.service

snap start kubelet.daemon
Started.
systemctl status snap.kubelet.daemon.service

Networking

The Container Network Interface (CNI) plugin is selected by passing kubelet the --network-plugin=cni

Logs

[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10248/healthz' failed with error: Get http://localhost:10248/healthz: dial tcp 127.0.0.1:10248: connect: connection refused.

Related terms

• Liveness probe: (livenessProbe)
• Readiness probe: (readinessProbe)
• systemctl stop snap.kubelet.daemon.service
• kubectl describe pods | grep Unhealthy
• Kubelet Container Runtime Interface (CRI)
• systemctl status kubelet

Activities

• CKA v1.15: Understand LivenessProbes and ReadinessProbes

News

• 05/2022 Kubernetes 1.24: dockershim removed from kubelet

See also

• kubelet, Pod Lifecycle Event Generator (PLEG), Kubelet conditions, /etc/kubernetes/kubelet.conf, /var/log/kubelet.log, Kubelet Container Runtime Interface (CRI), crictl, context deadline exceeded, E1122, E1124, Starting kubelet, NodeHasDiskPressure, NodeHasInsufficientMemory, rebooted, Node-pressure Eviction, Kubelet logs, manager: kubelet
• Kubernetes Components, kube-proxy, kube-scheduler, kube-apiserver, kubelet, kubectl, kubeadm, Kubernetes controller manager, Kubernetes controllers, Kubernetes Addons, Kubernetes Topology Manager
• Kubernetes: distributions, tools, CKA, CKS, Kubernetes interfaces: CSI, CNI, installation, workloads, networking, kubeadm, Kubernetes API, Kubernetes API Server, kubectl, kubeadm, kubelet, kube-proxy, Cloud services: EKS, GKE, TKE, DKS, Helm, Kubernetes RBAC, Kubernetes deployments, Minikube, Rancher, OpenShift, Charmed Kubernetes, Ingress, Kubernetes scheduler, Kubernetes Finalizers, logging, Kubernetes operator, Orka, kind:, Kubernetes namespaces, Kubernetes dashboard, Kubernetes Metrics Server, Field Selectors, CoreDNS, CRI, Kubernetes Topology Manager, Kubernetes governance: (SIG, KEP), Kustomize, controllers, ReadinessProbe, LivenessProbe, KOPS, K9s, Kui, k3s, ImagePullBackOff, PDB, EndPoints, Kots, metadata, Karpenter, Replicated.com, Kubernetes Authenticating, Kubernetes timeline, Changelog/Versions, service accounts, Kubernetes Pod Lifecycle, Kubernetes Conformance Certified, Kubernetes backup, Kubernetes Pod Security Admission, tEKS, Kubernetes events, Kubernetes ports, Kubernetes policies, Connect, addons, DoKC, Kubernetes control plane, Kubernetes Federation, Kubernetes info, Kubetest2, Sidecar (Kubernetes)